From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AB8JxZpDq0/cudeKr6PNJokV37KSbvOv5hcXJ942TkXOixvSxr47uV9PTwAcZzUeprMbRcHLwaw8 ARC-Seal: i=1; a=rsa-sha256; t=1526280757; cv=none; d=google.com; s=arc-20160816; b=Hf5GXi6biPKAORWzq1YsHNofSprgOQx2ivwrkdaNbxG8fsix4bXcI3sDhbLLCELBZe G1xJ0ey9djGaU4mSR7FTxQDg6wSFxThWbyBbUKnSs2T3jv87dzXfFRASy4rKJ1TxL8XG PQG2u1ISXwmn5nVKXGbJyHegqy0cmkhYQVfWbxs4FC3TQDB5l9NusmLAckh5DnEmXimR 5p4pVv61mOaoqOiKI+EyETmnaZ1SgbzuAnojQjzO8sL0V1TeWHR6U5AXAk6YwmBCj0uJ gZNelRHcxnZsd/IPesrnzC58vOhjDxr1avgt82sbTKxVLwrL+okhtpzqwOCE6zU9BSht 4ETA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:dkim-signature:arc-authentication-results; bh=PKxXLNibukgVUVDPzcyZrTNqIZrIfOglXNnF5dgYag4=; b=ZTCVWikNHYBEr93xO67W/4eUgJWaj2DlbyDUT+jBLYIBoEtOzTjPUoKLUprd5rGbLr fafPGLjtbIUm2rtIYTUjN+IBatlkIWaA0/s39QhPC2SCEtgtgxnZicg9r0ZyFkT4QrUi 7luC+kXe49ojXjUh3Yfjg7d9vldOxKvF3TY+yIPT6Z5uO4Buy8EFC1KIq/FZwYr8MQfI pvwFnouFV7Xnlq2vDZyt61mPOe60RdbTx0OMC87IhmL/iIoXQnTHc6ULsNfqWCxBh2op aW3X3qSJut92zL0Qo9EiMTxmVKQs6bUaw56KadM7E/d7+crnmHG/NLSD8P3m6insaIdd jBWA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=DIueHqYt; spf=pass (google.com: domain of srs0=ywzk=ib=linuxfoundation.org=gregkh@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=SRS0=ywzk=IB=linuxfoundation.org=gregkh@kernel.org Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=DIueHqYt; spf=pass (google.com: domain of srs0=ywzk=ib=linuxfoundation.org=gregkh@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=SRS0=ywzk=IB=linuxfoundation.org=gregkh@kernel.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Steven Rostedt (VMware)" Subject: [PATCH 4.4 46/56] tracing: Fix regex_match_front() to not over compare the test string Date: Mon, 14 May 2018 08:48:51 +0200 Message-Id: <20180514064759.044491014@linuxfoundation.org> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180514064754.853201981@linuxfoundation.org> References: <20180514064754.853201981@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1600421234253584189?= X-GMAIL-MSGID: =?utf-8?q?1600421372066307073?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Steven Rostedt (VMware) commit dc432c3d7f9bceb3de6f5b44fb9c657c9810ed6d upstream. The regex match function regex_match_front() in the tracing filter logic, was fixed to test just the pattern length from testing the entire test string. That is, it went from strncmp(str, r->pattern, len) to strcmp(str, r->pattern, r->len). The issue is that str is not guaranteed to be nul terminated, and if r->len is greater than the length of str, it can access more memory than is allocated. The solution is to add a simple test if (len < r->len) return 0. Cc: stable@vger.kernel.org Fixes: 285caad415f45 ("tracing/filters: Fix MATCH_FRONT_ONLY filter matching") Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Greg Kroah-Hartman --- kernel/trace/trace_events_filter.c | 3 +++ 1 file changed, 3 insertions(+) --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -322,6 +322,9 @@ static int regex_match_full(char *str, s static int regex_match_front(char *str, struct regex *r, int len) { + if (len < r->len) + return 0; + if (strncmp(str, r->pattern, r->len) == 0) return 1; return 0;